<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="/vue.js"></script>
</head>
<body>
    <div id="app">
        <ol>
        <todo-item></todo-item>
    </ol>
    </div>
    

    <script>
        Vue.component('todo-item', {
            template: '<li>this is a todo item</li>'
        });
        var app = new Vue({
            el: '#app',
            data: {

            }
        })
    </script>
</body>
</html>